1. Field of the Invention
The present invention relates to explosive containment systems. In particular, the invention relates to relatively light weight containment systems which can be used to contain or mitigate the effects of explosively disseminated chemical and/or biological devices.
2. Description of the Related Art
Several countries, many of them hostile to the United States and its allies, currently possess or are seeking to develop the capability to produce nuclear, biological and/or chemical weapons of mass destruction (WMD) and the means to deliver them. Many of these countries also advocate terrorism as a means to achieve their goals. In order to respond to the threat of terrorism using weapons of mass destruction, responding agencies at all levels of government (i.e. local, state and federal) must be adequately prepared to mitigate the hazards to the public and the environment in a timely manner. Terrorists and extortion bombings have always been a problem for law enforcement officials, not only on a national scale, but on an international scale as well. A particular problem to date has been the manner of disposing of a detected bomb or explosive device.
Perhaps the largest single cause of bodily injury in detected explosive devices comes from blasts which take place as the law enforcement officials first on the scene attempt to disarm, or render safe, the bomb or device in order to protect the public and surrounding property. In some cases, the procedure is to detonate the device on site by use of smaller explosive or countercharge to set off the device's main explosive charge. The result is an explosive blast that may cause significant personal or property damage in the immediate area.
Improvised explosive devices (IED's) are the main tools of the trade for some terrorist groups and produce casualties or damage to property through three dynamic processes. The explosion produces high velocity metal fragments or shrapnel, a high velocity compression or blast wave, and a high temperature combustion event termed a fireball. Even small amounts of explosive can be deadly if enough high velocity fragments are disseminated after detonation.
Terrorists may deploy improvised dispersion devices (IDD's) which could effectively disperse chemical or biological hazards as vapors or aerosols. If the hazards are inspired by humans or animals downwind of the dispersion point, they can produce deleterious physiological effects including death.
For relatively small devices which contain either conventional explosives or a combination of an explosive device and chemical, biological, or radiological payload, it may be possible to place a ballistic blanket over the device to inhibit the hazardous effects from the IED or IDD. The difficulty with bomb blankets is that they are quite heavy. The weight of these blankets may require the use of a crane. The bomb blankets could also cause unwanted detonation by coming in contact with antihandling devices placed on the IED or IDD. In addition, conventional bomb blankets are not normally configured with standoff capabilities nor are they adequate in containing secondary hazards such as chemical or biological aerosols.
Since it is not practical to disseminate chemical or biological agents with large amounts of explosive, containment of the explosive is not as big a concern when dealing with chemical and biological devices. The chemical hazard is normally a vapor or off-gassing hazard, while the biological agent is an aerosolized particulate of respirable size. Although some work has been done in the area of containing individual hazards, it has been limited to passive dissemination systems through filtration systems and secondary containment systems.
In summary, prior art explosive containment systems are not well-suited for containment of chemical, biological or radiological agents. The systems often include only metal structures which are of considerable size and weight and are not likely to be man-portable. Furthermore, prior art explosive containment systems for use against improvised explosive devices (IED's) only attempted to contain the effects of the blast over-pressure, fireball and high velocity fragments. Applicants are unaware of previous attempts to mitigate or contain improvised dispersal devices disseminating chemical, biological or radiological hazards.
In view of the need to safely dispose of explosive devices which may contain chemical, biological and/or radiological agents, and further in view of the need to provide containment systems which can be quickly delivered and assembled at remote sites, new and improved explosive containment systems are still required. In sum, there is a need for explosion containment systems that include the wherewithal to mitigate and/or contain chemical, biological, radiological, and explosive hazards. The present invention addresses this need.